An endophytic Trichoderma‐based wettable powder formulation for biocontrol of apple stem cankers

Abstract

AbstractFungal stem cankers are common and destructive diseases in apple orchards. Cytospora cincta and Neoscytalidium dimidiatum are the apple canker causal agents in Iran. Formulated biocontrol agents of plant diseases are considered alternatives to synthetic pesticides in sustainable agriculture. The results showed that Trichoderma zelobreve T20 strongly inhibited the in vitro growth of C. cincta and N. dimidiatum. Wettable powder formulation (WPF) based on T. zelobreve T20 was developed to control apple canker caused by C. cincta and N. dimidiatum. The dual culture test showed that T20 inhibited C. cincta and N. dimidiatum growth by 55.19% and 44.07% respectively. T20 culture filtrate reduced the mycelial growth of C. cincta (72.22%) but showed no activity against N. dimidiatum. T20‐based WPF inhibited C. cincta (94.62%) and N. dimidiatum (14.71%) growth on detached branches of 2‐year‐old apple trees (golden delicious cultivar). Also, T20‐based WPF inhibited apple tree canker caused by C. cincta and N. dimidiatum by 82.8% and 60% respectively. The performance of T20‐based WPF on apple trees was significantly better than detached branches. The spore count of T20‐based WPF was about 71.54% of the original count after 4 months, marking its suitable shelf life. T20‐based WPF could be considered a promising control measure against apple canker pathogens.